Amyloid-β peptides, whose different alloforms are produced from cleavage of the amyloid precursor protein, form amyloid plaques in the brain of people with Alzheimer’s disease, and the oligomers of amyloid-β are considered to be the main neurotoxic agent in Alzheimer’s disease [29,30]. The gene discussed is APP; the disease is early-onset autosomal dominant Alzheimer disease.